PHILADELPHIA — The Eagles spent the day after Christmas claiming that the Cowboys’ Tony Romo’s absence in Sunday night’s win-or-go-home showdown won’t qualify as a gift.

Dallas spent another day with its starting quarterback in the trainer’s room and off the practice field and away from team meetings, as Romo tried to ease the pain in his back with an epidural injection and therapy.

Chip Kelly seemed as uninterested in Romo’s status as an opposing head coach preparing for a quasi-playoff game could, leaving it to defensive coordinator Bill Davis and his staff to decide how much film time it should dedicate to Romo and his understudy, veteran Kyle Orton.

“I don’t think this changes their offense much just because of who the backup is,” Kelly said Thursday. “I think they are going to stick to what they do. They obviously have playmakers in (receiver) Dez Bryant and (tight end Jason) Witten. They are going to run the ball with DeMarco Murray, who didn’t play against us in the first game.

“I don’t anticipate Kyle coming in and they start running the option up and down the field. I think they will stick to their plan. ... They have got a really good scheme offensively, so I don’t think it’s going to change what our approach is going to be.”

Cornerback Cary Williams echoed Kelly’s sentiments.

“I don’t think they can change or transform their offense this late in the year,” he said. “The two guys are pretty similar. It’s not like one of them is a predominantly running quarterback versus a pocket passer.

“I couldn’t care less what is going on in Dallas. What I do care about is being in Dallas Sunday night and getting a win.”

Witten, who has racked up most of his 9,664 career receiving yards courtesy of Romo passes, wasn’t going to sugarcoat the task his team faces if the veteran quarterback with the bad back isn’t under center at Cowboys Stadium. Despite a great deal of criticism about his ability to win a big game, Romo has the fifth-highest quarterback rating of all time (95.8). This season that rating is 96.7, as the 33-year-old has thrown for 3,828 yards, 31 touchdowns and only 10 interceptions after chucking an NFL-high 19 picks a year ago.

That said, Romo has only one career playoff win — in 2009 against the Eagles — and his ability to rally the Cowboys last weekend against the woeful Redskins after straining his back is high on his flimsy résumé of clutch performances.

“Tony is an elite, elite QB in the NFL,” said Witten, who is third in NFL history in career receiving yards for a tight end behind Tony Gonzalez and Shannon Sharpe and second in receptions (867) behind Gonzalez. “He has played at a high level this year. ... It was an unbelievable job by him last week, willing us to win that game against the Redskins. I know he’s working through it and would give anything to be out there if he can do it.”

Orton doesn’t exactly have a large big-game portfolio: zero playoff appearances, from getting benched for Rex Grossman as a rookie in Chicago, to losing his last four games Denver in 2009 as the Broncos went from 8-4 to out of the postseason, to getting off to a miserable start in 2011 and ceding Denver’s starting job to Tim Tebow.

Yes, you can indirectly blame Orton for the Tebow hype machine.

Throw on top that the Cowboys have entered the final regular-season game of each of the last two seasons with a chance to win the NFC East and lost to the Giants and Redskins, respectively, and Dallas has a grand piano of pressure latched to its back no matter the quarterback.

“There’s no question that being in those situations those last two years, it sits deep in your gut,” Witten said. “I think you need to take the emotions out of it. Our focus has to be on what does it take to execute.

“You have to eliminate the other emotions out of it so you can prepare and have a chance to win. I think that goes for both teams. When you go through that and come up short, it’s tough. But it’s a new year. You have to move forward.”